pyqtgraph 中有没有办法设置一个级别，例如FillBetweenItem？

Question

在我的应用程序中，我有很多来自不同类型的不同 FillBetweenItems，我不想每次都删除并再次绘制所有项目。我想使用 curve1.setData() 和 curve2.setData()。我想为每个 class 设置一个级别：例如class1 的 FillBetweenItem 应始终位于 class2 的 FillBetweenItem 之上。而 Class3 将始终在 class2 下面。有什么我想念的吗？

import pyqtgraph as pg

class RedClass:
    def __init__(self, ax = None):
        self.ax = ax
        self.lowerCurve = None
        self.upperCurve = None
        self.fillItem = None
    def draw(self, ax = None):
        pen = pg.mkPen(None)
        if self.lowerCurve is None:
            self.lowerCurve = self.ax.plot([1,2],[1,1], pen = pen)
        else:
            self.lowerCurve.setData(x = [1,2], y =  [1,1])
        if self.upperCurve is None:
            self.upperCurve = self.ax.plot([1,2],[3,3], pen = pen)
        else:
            self.upperCurve.setData(x = [1,2],y =  [3,3])
        if self.fillItem is None:

            self.fillItem = pg.FillBetweenItem(self.lowerCurve, self.upperCurve, brush = pg.mkBrush('r'))
            self.ax.addItem(self.fillItem)
class GreenClass:
    def __init__(self, ax = None):
        self.ax = ax
        self.lowerCurve = None
        self.upperCurve = None
        self.fillItem = None
    def draw(self):
        pen = pg.mkPen(None)
        if self.lowerCurve is None:
            self.lowerCurve = self.ax.plot([1.5,2.5],[1.5,1.5], pen = pen)
        else:
            self.lowerCurve.setData(x =[1.5,2.5], y =  [1.5,1.5])
        if self.upperCurve is None:
            self.upperCurve = self.ax.plot([1.5,2.5],[2.5,2.5], pen = pen)
        else:
            self.upperCurve.setData(x = [1.5,2.5],y = [2.5,2.5])
        if self.fillItem is None:
            self.fillItem = pg.FillBetweenItem(self.lowerCurve, self.upperCurve, brush = pg.mkBrush('g'))
            self.ax.addItem(self.fillItem)


if __name__ == '__main__':
    from PySide2.QtWidgets import QApplication
    import sys
    app = QApplication(sys.argv) 
    ax = pg.PlotWidget()
    greenOne = GreenClass(ax = ax)
    redOne = RedClass(ax = ax)
    #time of draw call determines which class is plotted on top
    redOne.draw()
    greenOne.draw()
    ax.show()
    sys.exit(app.exec_())

这取决于我是先调用 redOne.draw() 还是先调用 greenOne.draw() 什么颜色会显示在顶部：

有没有办法设置，例如红色 class 的 Fillbetween 项总是在绿色项之上的级别？还是我必须照顾好每一件物品？

Answer 1

您必须设置 ZValue：具有较高 ZValue 的项目将始终位于具有较低 ZValue 的项目之前：

# ...
redOne.draw()
greenOne.draw()

<b>greenOne.fillItem.setZValue(0)
redOne.fillItem.setZValue(1)</b>

ax.show()
# ...

pyqtgraph 中有没有办法设置一个级别，例如FillBetweenItem？

Is there a way in pyqtgraph to set a level of e.g. a FillBetweenItem?

python

pyqtgraph